Wednesday, 16 October, 2019




(1) Cereals : These are the members of family Gramineae and grown for their edible seeds. They are characterised by the presence of caryopsis a type of fruit in which seed wall becomes fused with the ovary to form the husk. The true cereals are the following :

(i) Wheat (Triticum aestivum) : Wheat is the chief cereal used by man as food from ancient times. It is an annual grass and the inflorescence is a terminal spike consisting of 15–20 spikelets. In India, its cultivation is confined to north-west regions. The important varieties of wheat, grown in India are Sonalika, Sharbati, Sonara, Lerma Roja, Sonara 64 etc.; Triticale hexaploides, a man made variety is also cultivated; wheat is used mostly for human consumption; the flour is chiefly used for making bread, biscuits etc.; wheat straw is used in packing and as fodder.

(ii) Maize (Zea mays) : It is the second important cereal crop. Maize is a tall annual grass attaining a height of 4 to 10 feet; plants are monoecious. In India common varieties grown are Sona, Vijay, Jawahar, Amber etc. The maize grains are very nutritious; they contain high percentage of easily digestible carbohydrates, proteins and fats; the grains are also used in the manufacture of corn starch, glucose and alcohol; also used as a chief food for livestock; the fibre from stem and spathe is used in paper industry.

(iii) Rice (Oryza sativa) : Rice is the principal food crop of millions of people of the world. The rice plant is an annual grass attaining a height of 2–4 feet and produces a panicle, an inflorescence consisting of a number of fine branches; it grows best on damp soils where it can be flooded. The rice grains are used as a food after cooking; stem, husk etc., are used as fodder; grain is also used in the manufacture of alcoholic beverages.

(iv) Sorghum (Sorghum vulgare) : Sorghum is staple food for millions of peoples in Asia and Africa. It is a tall annual plant attaining a height of 6–12 feet; the stem is stout and the panicle much-branched. The grains are made into flour, often mixed with wheat, forming a nutritious food. The plants are used as fodder, in the manufacture of brushes, syrup and also in the paper industry.

(v) Barley (Hordeum vulgare) : Barley is an annual plant attaining a height of 3 feet. The inflorescence is a spike; the grains may be white, purple or red and are covered with husk. Barley is used in the preparation of bread, cakes after mixing it with wheat flour; straw is used as a livestock feed; also used as a source of malt, to be used in the manufacture of beer, whisky, alcohol etc.

(vi) Pearl millet or Bajra (Pennisetum typhoides) : It is cultivated almost throughout India. The plants attain a height from 6–12 feet and the dark-brown spikes, 15–25 cm in length, occur in clusters. It is an important food for poor people in our country; the flour is used for making chapatis; the plants are also used as fodder.

(2) Sugar : Sugars are the end products of photosynthesis in green plants. Cane-sugar or sucrose is the main commercial sugar used world over for sweetening various food products. Some of the important sugar yielding plants are as follows :

(i) Sugarcane (Saccharum officinarum) : It belongs to family Gramineae and is the chief source of sugar in India. The plant reaches a height of 6 to 12 feet and a diameter 1 to 2 inches; the stem is solid with many fibrous strands and contains juice; the stems are cut close to the ground and are then sent to sugar mills for the extraction of sugar. Molasses is used in the manufacture of rum and industrial alcohol. Molasses is the mother liquor, left after extraction of sugar crystals.

(ii) Sugar-beet (Beta vulgaris) : It belongs to family Chenopodiaceae and is the source of sugar in cold countries. The sugar-beet is a biennial herb with white tap root. Sugar is extracted from the fleshy roots which contain 15–20% of sucrose. In India sugar-beet is not much used as a source of sugar but the roots and leaves are used as vegetables.

(3) Fibres : The fibre crops of the world rank second in importance to the food crops. Fibres are thread-like sclerenchymatous tissues obtained from different parts of the plant body. They are usually long with thick walls and pointed ends; the thickening of the walls is either due to the deposition of lignin or cellulose. Some of the important commercial fibres are as follows :

(i) Cotton (Gossypium sp. – family Malvaceae) : Cotton is the most important commercial textile fibres. It is used for a variety of purposes, especially in the manufacture of a large proportion of the clothing. Fibres are produced by the seed coats of various species of Gossypium and when separated from the seed are known as `lint’. Fibres are also used for making ropes, twines and threads; raw cotton is also used for stuffing pillows and cushions.

(ii) Jute (Corchorus capsularis  and C. olitorius – family Tiliaceae) : It is a very valuable bast fibre and is second in use to cotton. The fibres are extracted by the process of retting in which the branches of plants are dipped in water for few days; after retting fibres are separated. Jute fibres are used for making gunny bags, packing cloth, carpets, cordage, curtains etc.

(iii) Sunn hemp (Crotolaria juncea-family Papilionaceae) : The plants are extensively cultivated in India. The long fibrous strands are made up of lignified phloem sclerenchyma cells which are obtained after retting. The fibres are used in the manufacture of ropes, canvas, nets, cordages etc.

(iv) Flax (Linum usitatissimum – family Linaceae) : The fibres are very strong, silky, short in length and are formed in the pericycle of the stem. They are made up of pure cellulose. Flax fibres are used in the manufacture of linen cloth, carpets, canvas, cigarette paper, insulating materials etc.

(v) Hemp (Cannabis sativafamily Cannabinaceae) : The fibres are obtained from the pericycle after retting. The hemp fibres are long, strong and durable but lack flexibility. It is used for the manufacture of ropes, cables, nets, canvas etc.

(vi) Coir (Cocos nuciferafamily Palmae) : It is obtained from the fibrous mesocarp of the fruit; the fruits are dipped in marine water for many months and then beaten to separate the fibres. Coir is used for making brushes, doormats, carpets, sacs, bags, cordage etc.

(4) Oils : Oils are the complex chemical compounds which consists of hydrocarbons, esters, alcohols, aldehydes etc. The oils are of two kinds :

(i) Essential oils                          (ii) Fatty oils

There are several species of plants yielding both edible and industrial oils. Some of the important oils are :

(a) Groundnut oil : It is obtained from the seeds of Arachis hypogea -family Papilionaceae; refined oil is used in cooking and oil is converted into vegetable ghee by dehydrogenation.

(b) Sesame or Til oil : It is obtained from the seeds of Sesamum indicum – family Pedaliaceae; oil is used in cooking, medicine, soap etc.

(c) Coconut oil : It is obtained from the dry Kernel of the seed of Cocos nucifera – family Palmae; oil is used for cooking, as hair oil, and in the manufacture of soaps, shampoo, cosmetics etc.

(d) Mustard oil : It is obtained from the seeds of Brassica campestris – family Cruciferae; oil is chiefly used for cooking purposes.

(e) Castor oil : It is obtained from the seeds of Ricinus communis – family Euphorbiaceae; oil is used in medicines, as lubricant and also in making soaps.

(f) Soyabean oil : It is obtained from the seeds of Glycine max – family Papilionaceae; raw oil is used in the manufacture of soap, varnishes, paints etc.; refined oil is used for cooking purposes.

(g) Linseed oil : It is obtained from the seeds of Linum usitatissimum – family Linaceae; oil is used in making paints, varnishes, soaps etc.

(5) Pulses : These are the members of family Leguminosae which is characterised by a type of fruit i.e., legume. Legumes or pulses are highly proteinaceous; they form excellent green manures as they are having root-nodules for nitrogen fixation. Some of the important pulses are as follows :

(i) Pea (Pisum sativum) : It is grown all over India during winter months. The plant is an annual herb climbing by means of tendrils. The seeds are eaten after cooking as vegetable; plants are used as valuable fodder.

(ii) Gram or Chana (Cicer arietinum) : It is cultivated all over India as an important pulse. The plant is a bushy annual and matures in about three months. The seeds are eaten as dal and the flour which is commonly called as besan is used in the preparation of sweets and other foodstuffs; the plants and seeds are also used as cattle feed.

(iii) Pigeon pea or Red gram or Arhar (Cajanus cajan) : It is widely cultivated in India and is grown as a pure crop or mixed crop. The plant is a perennial shrub. Dry grains are used as dal; leaves form a valuable fodder; branches are used for making baskets.

(iv) Ground nut or Moongphali (Arachis hypogea) : The plant is a bushy annual with underground fruits. Groundnuts are very nutritious as they are rich is proteins. Seeds are used after roasting for preparation of peanut butter; groundnut oil is largely used as cooking oil.

(v) Black gram or Urd (Phaseolus mungo) : It is the one of the best pulses grown all over India. The plant is a trailing annual. It is used as dal; flour is used in the preparation of papads and biscuits; seeds and straw form a valuable cattle feed.

(vi) Soyabean (Glycine max) : The seeds of this plant are the protein richest, natural vegetable food known. It is cultivated all over India. The plant is a small, bushy, erect or prostrate annual. It has 30-60% protein content. Seeds are used green or dry; soya milk, soya cheese etc. are prepared from the seeds; soyabean flour is used in bakery, ice cream etc.

(vii) Green gram or Moong (Phaseolus radiatus) : It is cultivated as an important pulse crop in Uttar Pradesh, Madhya Pradesh, Rajasthan, Bihar and Bengal. The green pods are eaten as vegetable and seeds are used as dal. The entire plant is used as cattle feed.

(6) Medicinal Plants : Most of the medicinal plants are wild; these plants are collected and sent to the centres of researches to work out their medicinal value. A good number of them are cultivated on commercial basis. Some of the important drug yielding plants are :

(i) Opium (Papaver somniferumfamily Papaveraceae) : The plant is an erect herb having large globose capsules. Opium is the latex of unripe fruits. The opium contains several important alkaloids such as morphine, codeine, narcotine, thebaine, neopine etc. The opium has narcotic and sedative effect and is largely used to relieve pain as an intoxicant. Heroine is a derivative of opium (morphine).

(ii) Rauwolfia (Rauwolfia serpentinafamily Apocynaceae) : It is an erect, perennial undershrub. The dried roots are an important source of an alkaloid reserpine and other alkaloids are serpentine, serpentinine, rauwolfine etc. The alkaloid reserpine is used in several patent drugs, as it has a depressant action on central nervous system and produces sedation and lowering of blood pressure.

(iii) Cinchona (Cinchona officinalis family Rubiaceae) : It is a famous quinine-yielding plant. Quinine is the most important drug obtained from the bark of this plant and also from other species i.e., C. ledgerina, C. officinalis and C. cordifolia. Bark of these plants contains about 30 alkaloids including quinine, cinchonine, quinidine and cinchinidine, all of which are used in medicine. Quinine has been a great boon to mankind, as it is the only adequate cure for malaria.

(iv) Belladona (Atropa belladonafamily Solanaceae) : Belladona drug is obtained from the leaves of this plant. The plant is a perennial herb. Belladona is used extremely to relieve pain; besides this leaves contain several alkaloids chief among which is atropine, used to dilate pupil of the eye.

(v) Ephedrine (Ephedra equisetina and E. sinicafamily Gnetaceae) : Ephedra is a leafless shrub. The entire plant is used in the extraction of this drug. Ephedrine is used to cure asthma, colds and hay fevers.

(vi) Aconite (Aconitum napellus family Ranunculaceae) : Aconite is obtained from the tuberous roots of this plant. Aconite relieves pain due to neuralgia, rheumatism and inflamed joints; it is also used as a tonic and sedative.

New world and Old world crops before 1492

New World Old World New World Old World
Maize Wheat Papaya Coconut
Potato Rice Avocado Cabbage
Tapioca Barley Pineapple Radish
Kidney bean Oat Custard apple Carrot
Lima bean Rye Guava Onion
Sunflower Sorghum Sapota Garlic
Peanut Lentil Cashew Spinach
Tomato Pea Cotton Cucumber
Squash Soyabean Quinine Brinjal
Pumpkin Mustard Cocoa Beet
Red Pepper Olive Coca Sugarcane


Some important Cereals and Millets

English name / Common name Botanical name Family
(A) Major cereals
1. Wheat (Gehoon) Triticum vulgare = T. aestivum Poaceae (Gramineae)
2. Maize (Corn, Makka) Zea mays Poaceae
3. Rice (Dhaan, Chawal) Oryza sativa Poaceae
4. Barley (Jau) Hordeum vulgare Poaceae
5. Oat (Jai) Avena sativa Poaceae
6. Rye Secale cereale Poaceae
(B) Millets  
7. Finger millet (Ragi) Eleusine coracana Poaceae
8. Pearl millet (Bajra) Pennisetum typhoides Poaceae
9. Sorghum (Jowar) Sorghum vulgare Poaceae

Some important Legumes

Common name Indian name Botanical name Special features
1. Pigeon pea/Red gram / Congo pea Arhar Cajanus cajan (= C. indicus) Seeds extensively used in the form of split pulse (dal) especially in South India.
2. Chick pea / Bengal gram/ Gram / Garbanzos Chana Cicer arietinum Seeds eaten raw, roasted, or boiled in the form of dal; Flour called besan, plus ghee and sugar used for making sweets.
3. Cluster bean Guar Cyamopsis tetragonoloba Young tender pods used as vegetables.
4. Horse gram Dolichos uniflorus Poor man’s pulse in South India; Often used as feed for cattle and horses.
5. Hyacinth bean Sem Dolichos lablab Young pods and tender beans used as vegetables
6. Chickling vetch / grass pea Khesari dal Lathyrus sativus Cheapest pulse; consumed by poor classes in India. Serious disease Lathyrism (paralysis of lower limbs) results from excessive and prolonged consumption of khesari dal. The seeds contain osteotoxin B–amino propronitrile (BPN) and water soluble neurotoxin B–N–oxalyl amino alamine (BOAA).
7. Lentil Masoor,                Malka masoor Lens esculenta/ Lens culinaris Most nutritious of all pulses; Protein content high, proteins easily digestible; unripe pods used as green vegetable.
8. Common bean / French bean / Kidney bean Vilayati sem Phaseolus vulgaris Green immature pods used as vegetable. Straw used as cattle feed.
9. Black gram Urd Phaseolus mungo (=Vigna mungo) Rich in phosphoric acid, used as dal; used with rice for idli and dosa. Chief constituent of Papar and Vari.
10. Green gram / Golden gram Mung Phaseolus aureus /             P. radiatus (Vigna radiata) Used as dal; seeds fried and salted used as snacks.
11. Moth bean Moth Phaseolus aconitifolius Young pods eaten as vegetable. Ripe seeds eaten as dal.
12. Pea Matar Pisum sativum Seeds used as vegetable after cooking or mixed with various vegetables.
13. Cow pea Lobia Vigna unguiculata (= V. sinensis) Seed eaten cooked as vegetable; immature pods also cooked as vegetables.
14. Soyabean Soyabean Glycine max (= G. soja = G. hispida = Soja max) Seeds richest in protein; Grinding boiled seeds with water yields soyabean milk (nutritious like cow’s milk, fit for infants) Soya–sauce is obtained by fermenting soyabean and rice flour with Aspergillus oryzae.

Some important Fruits

Common Name Indian name Botanical name & Family Special features
1. Lime (a)  Kaaghzi Nimbu

(b)  Nimbu

Citrus aurantiifolia (Rutaceae)

C. aurantiifolia var. bergamia

Hesperidium; Citric acid in fruits,

Hesperidium; Unripe fruit is digestive,

2. Sour or Seveille orange Khatta Citrus aurantium var. bigardia (Rutaceae) Hesperidium; Rich in provitamins A and B.
3. Sweet orange Mausambi/Malta Citrus sinensis (Rutaceae) Hesperidium; Fruit juice quenches thirst, improves apetite, given to patients;
4. Mandarin orange/ Tangerine Santara Citrus reticulata Hesperidium; Highly nutritious, rich in calcium;
5.  Shaddock/Pummelo Chakotra Citrus maxima C. grandis (Rutaceae) Hesperidium; Fruits edible, neither sour nor bitter;
6. Grape fruit Citrus paradisi (Rutaceae) Hesperidium; Canned and frozen;
7. Apple Sev Malus pumila (=Pyrus malus = Malus sylvestris) (Rosaceae) Pome; Fleshy thalamus edible, Malic acid is chief acid; characteristic smell due to esters and essential oils.
8. Apricot Khubani Prunus armeniaca (Posaceae) Drupe, Epicarp and mesocarp edible.
9. Peach Aroo Prunus persica (Rosaceae) Drupe; eaten raw, also canned
10. Pear Nashpati Pyrus communis (Rosaceae) Pome; rich in sugar, eaten raw and canned
11. Plum Alucha Prunus domestica (Rosaceae) Drupe; Epicarp and mesocarp edible.
12. Japanese Medlar Loquat Eriobotrya japonica (Rosaceae) Mesocarp edible, Drupe
13. Mango Aam Mangifera indica (Anacardiaceae) Drupe; Fleshy mesocarp edible, eaten raw; pickled, jams prepared, important source of vitamins A.
14. Banana Kela Musa sapientum = M. paradisiaca (Musaceae) Berry; good source of vitamins A, C; rich in minerals and sugars
15. Custard apple Sharifa Annona squamosa Etaerio of berries, fruit eaten fresh
16. Cherimoya Hanumanphal Annona cherimola (Annonaceae) Etaerio of berries, fruit eaten fresh
17. Pineapple Ananas Ananas comosus (Bromeliaceae) Sorosis; fleshy axis, bracts, perianth and seeds edible.
18. Date palm Khajur Phoerix dactylifera (Palmae) Drupe; rich in sugars, a fermented drink (toddy) is prepared from the sap.
19. Grapes Angoor Vitis vinifera


Berry; eaten raw, used for making raisins and wine 18–25% sugar-mostly glucose and fructose.
20. Guava Amrood Psidium guajava (Myrtaceae) Berry cheap and rich source of vitamin C and calcium.
21. Jumbolan Jamun Syzygium cumini (=Eugenia jambolana) (Myrtaceae) Berry; seeds useful in diarrhoea, dysentry and diabetes.
22. Litchi Litchi Litchi chinensis (Sapindaceae) One-seeded nut; fleshy aril of seed edible.
23. Mulberry Shehtoot Morus alba (Maraceae) Sorosis, juicy inflorescence edible; silkworm reared on leaves.
24. Fig Anjeer Ficus carica (Moraceae) Syconus; fruit edible.
25. Muskmelon Kharbuja Cucumis melo (Cucurbitaceae) Pepo; fruit eaten raw.
26. Watermelon Tarbooz Citrulus vulgaris (Cucurbitaceae) Pepo; fruit eaten raw.
27. Papaya Papeeta Carica papaya (Caricaceae) Berry; Raw fruit eaten; contains proteins, minerals, vitamins and enzyme papain
28. Pomegranate Anaar Punica granatum (Punicaceae) Berry; with edible aril, Dried seeds (anardana) used as flavouring substance.
29. Phalsa Phalsa Grewia asiatica (Tiliaceae) Drupe, eaten raw
30. Jujube Ber Zizyphus mauritiana (Rhamnaceae) Drupe, eaten raw.
31. Emblic Amla Emblica officinalis (=Phyllanthus emblica) (Euphorbiaceae) Rich in vitamin C, used for controlling indigestion.
32. Wood-Apple Bael Aegle marmelos (Rutaceae) The ripe fruits is aromatic, used as laxative.

Some common Vegetables

English Name Hindi name Botanical name & Family Special remarks
A. Root Vegetables    
1. Beets Chukander Beta vulgaris (Chenopodiaceae) Roots and leaves used as salad and vegetables.
2. Carrot Gajar Daucus carota (Umbelliferae) Used as salad and vegetable, contains carotene A precursor of Vitamin A.
3. Radish Moolee Raphanus sativus (Cruciferae) Used as salad; leaves used as vegetable; rich in vitamins A and C.
4. Turnip Shaljam Brassica rapa (Cruciferae) Characteristic flavour due to presence of volatile is othiocyanates used as salad and vegetable.
5. Sweet potato Shakarkandi Ipomoea batatas (Convolvulaceae) Tuberous root edible, good raw material for industrial alcohol, starch and glucose.
6. Cassava / Tapioca Saakarkand Manihot esculenta

=M. utilissima (Euphorbiaceae)

Tubers rich in calcium and vitamin C alongwith starch source of tapioca starch; staple food of many people; in India concentrated on west coast especially in Kerala.
B. Underground Stems  
7. Garlic Lahsun Allium sativum (Liliaceae) Pungent smell due to allicin-antiseptic and bactericide-used as flavouring vegetables.
8. Onion Pyaz Allium cepa (Liliaceae) Fleshy leaves of bulb rich in minerals and vitamins; eaten raw with meals; added to dals.
9. Potato Aaloo Solanum tuberosum (Solanaceae) Cheap source of starch, excellent source of vitamin C and minerals.
10. Taro Arvi Colocasia esculenta Rhizome starchy, tuberous, edible.
11. Artichoke Hathichuk Helianthus tuberosus (Compositae) Edible tuberous stem underground; source of levulose-sweetening agent used by diabetics.
C. Herbage Vegetables  
12. Cabbage Band Gobhi Brassica oleracea var. capitata (Cruciferae) Vegetative bud consisting of compaction of leaves edible eaten raw or cooked.
13. Cauliflower Phoolgobhi Brassica oleracea var. botrytis (Cruciferae) Inflorescence comprises hypertrophied flower stalks and abortive flowers eaten after cooking.
14. Lettuce Salad Lactuca sativa (Compositae) Leaves eaten as salad; rich in vitamins A and E.
15. Spinach Palak Spinacea oleracea (Chenopodiaceae) Compact rosette of leaves eaten cooked; rich in vitamin A and minerals.
16. Celery Celera Adium graveolens var. dulce (Umbelliferae) Leaf stalks contain good quantities of starch, used in salads, stews and soups.
17. Asparagus Asparagus officinale (Liliaceae) Shoots (Cladodes) consumed green; rich source of vitamins A, B1, B2 and C.
D. Fruit Vegetables  
18. Tomato Tamatar Lycopersicon esculentum             (= Solanum lycopersicum) (Solanaceae) Salads and cooked vegetables; Rich in Vitamin C, A, B, B2
19. Brinjal/Egg plant Baingan Solanum melongena (Solanacea) Fruit cooked as vegetable; rich in iodine.
20. Lady’s finger/Okra Bhindi Abelmoschus esculentus

= Hibiscus esculentus (Malvaceae)

Unripe fruit cooked as vegetable.
21. Cluster bean Guar Cyamopsis tetragonoloba (Papilionaceae) Immature green pods seeds edible; guar gum from seed.
22. Hyacinth bean Sem Lablab purpureus (=Dolichos lablab) (Papilionaceae) Green pods and seeds eaten as vegetable.
23. Wax or white gourd Petha Benincasa hispida (Cucurbitaceae) Confectionery and vegetable.
24. Squash melon Tinda Citrullus lanatus var. fistulosus (Cucurbitaceae) Cooked as vegetable.
25. Snapmelon Phoot, kachra Cucumis melo var. momordica (Cucurbitaceae) Cooked as vegetable.
26. Long melon or Snake cucumber Kakri or Tar Cucumis melo var. utilissimus (Cucurbitaceae) Salad.
27. Cucumber Kheera Cucumis sativus (Cucurbitaceae) Salad.
28. Winter squash Vilayati Kaddu Cucurbia maxima (Cucurbitaceae) Cooked vegetable.
29.Pumpkins Sitaphal, Halwa Kaddu or Kanshiphal Cucurbita moschata Cooked vegetable and sweet.
30.Summer squash or Marrow Chappan kaddu Cucurbita pepo (Cucurbitaceae) Cooked as vegetable.
31. Bottle gourd or Calabash Lauki, ghia Lagenaria siceraria (Cucurbitaceae) Cooked vegetable and containers.
32. Ridged or Ribbed sponge gourd, dishcloth gourd Kali tori Luffa acutangula (Cucurbitaceae) Cooked vegetable.
33. Smooth sponge gourd or Loofah Ghia tori Luffa cylindrica (Cucurbitaceae) Cooked vegetable and sponges for bath.
34. Bitter gourd or balsam pear Karela Momordica charantia (Cucurbitaceae) Cooked vegetables and pickles.
35. Pointed gourd Parwal, parmal Trichosanthes dioica (Cucurbitaceae) Cooked vegetable.

Some important Nuts

Common name Hindi name Botanical name (Family) Special features
1. Cashewnut Kaajoo Anacardium occidentale (Anacardiaceae) Kidney – shaped seeds present in kidney shaped nuts (cashew nut) borne on juicy pear-shaped fruit (cashew apple). The seed eaten raw or roasted. Cashew apple juice fermented to make cashew wine.
2. Walnut Akhrot Juglans nigra (Juglandaceae) (a)  Kemels eaten as such or added to confectionary and ice creams, custards etc.

(b)  Tree bark used as dundasa for cleaning teeth.

3. Almond / Sweet almond Badam Prunus dulcis (= Prunus amygdalus var. dulcis) (Rosaceae) Seeds eaten raw, added to confectionary, custard etc. Badam roghan – an oil extracted from sweet almond is medicinally important.
4. Bitter almond Karua badam Prunus amygdalus var. amara (Rosaceae) Contain bitter poisonous glucoside-amygdalin.
5. Pistachio nut/ Green almond Pistaa Pistacia vera (Anacardiaceae) Kernels eaten salted, roasted used for decorating and flavouring confectionary, ice creams etc.
6. Coconut Nariyal/Gola Cocos nucifera (Palmae) Kernel called copra; yields coconut milk; food and oil from kernel.
7. Pinenut Chilogja/Neja Pinus gerardina (Pinaceae) Edable part is kernel.


Some important Essential oils

Common Name Hindi name Botanical name Special features
1. Jasmine oil Juhi Jasmine auriculatum (Oleaceae) Fragrant flowers yield jasmine oil used in perfumed oils and attars.
2. Khas Khas oil Khus Khus Vetiveria zizanioides (Gramineae) Roots yield a khus khus oil used in perfumes, soaps, sherbets; roots used for mats for air coolers.
3. Lavender Lavandula angustifolia (Labiatae) Flowers yield oil for perfumes, toilet soaps, toilet ponders, Lavender water etc.
4. Rose oil Gulab Rosa damascena (Rosaceae) Petals yield oil or roses, used in rose water attar; petals used for gulkand.
5. Sandalwood oil Chandan Santalum album (Santalaceae) Heartwood yields oil, roots also are rich source of oil; oil used for toilet soaps, face creams, perfumery and also religious ceremonies.
6. Camphor Kapoor Cinnamomum camphora (Lauraceae) Wood yields camphor (camphor gum) used in perfumery and medicines.
7. Lemongrass oil Cymbopogon citratus (Graminaee) Leaves yield oil which contain citral; used in manufacturing perumes (lonone), soaps, cosmetics etc.
8. Eucalyptus oil Eucalyptus globosus (Myrtaceae) Dried leaves yield oil used for perfumery, treatment of asthma and bronchitis.
9. Cedarwood oil Juniperus macropoda (Pinaceae) Heart wood yields oil used for perfumery, clearing agent in the preparation of microscopic slides.
10. Peppermint oil Mentha piperata (Labiatae) Leaves yield oil used in perfumery.
11. Champaca oil Michelia champaca (Magnoliaceae) Flowers yield oil used in perfumery.
12. Clove oil Syzygium aromaticum (Myrtaceae) Unopen flower buds yield oil used in perfumes and medicines.
13. Geranium oil Pelargonium graveolens Oil from leaves used in perfumery.

Some Fatty oils yielding plants

Common name Hindi name Botanical name Special features
1. Coconut Nariyal Cocos nucifera (Palmae) Endosperm yields coconut oil used as cooking oil, hair oil, etc.
2. Mustard Sarson Brassica campestris var. sarson (Cruciferae) Oil from seeds used in cooking, pickes; oil cake used as cattle feed.
3. Ground nut Moongphali Arachis hypogea (Papilionaceae) Seed (cotyledones) yield non-drying oil used as cooking medium; large quantities used for manufacturing vegetable ghee; oil cake used as cattle feed.
4. Safflower Kusum Carthamus tinctorius (Compositae) Seed oil edible, rich in PUFA (poly unsaturated fatty acid), prescribed for heart patient, for it does not increase cholesterol; flowers yield dye used to colour foods and cloth.
5. Sesame, Gingelly Til Sesamum indicum (Pedaliaceae) Seed oil used as cooking medium; oil cake used as cattle feed; defatted seeds are rich source of protein.
6. Soyabean Soyabean Glycine max (Papilionaceae) Seed oil is edible; germinated seeds rich in vitamin C Soymeal rich in proteins; lecithin-a, by-product of oil industry, used as stabilising agent in cosmetics, medicines, plastics etc.
7. Sunflower Surajmukhi Helianthus annuus (Compositae) Seeds yield an oil; used as cooking medium; oil cake used as cattle feed.
8. Oil palm/African oil palm Elaeis guineensis (Palmae) The fleshy mesocarp of the fruits yields edible oil which is also used in the manufacture of soaps, candles, lubricants as well as a fuel for internal combustion engines.
9. Castor Arandi Ricinus communis (Euphorbiaceae) Seeds yield oil used as purgative lubricant and in soap industry.
10. Cotton Kapas Gossypium sp. (Malvaceae) Seeds yield oil used for cooking.
11. Linseed Alsi Linum usitatissimum (Linaceae) Seeds yield oil forming a tough elastic film on oxidation; used for making paints and printing inks.
12. Olive Jaitoon Olea europea (Oleaceae) Fruits yield edible oil.


Some more Fibre-yielding Plants

Common name Hindi name Botanical name and Family Special features
1. Flax Alsi Linum usitatissimum (Linaceae) Pericycle fibres : soft/bast, used for bags, ropes, carpets paper.
2. Sunn hemp Sunn Crotolaria juncea (Leguminosae) Fibres from region outside cambium used for canvas, rope, nets.
3. Hemp Bhang Cannabis sativus (Cannabinaceae) Fibres from bark; used for brush, ropes, carpets, cordage, sacks, bags.
4.  Munja Munj Saccharum munja (Poaceae) Fiber from stem and leaves, lower part of stem used for making furniture; upper part for cordage, baskets.
5. Coir Nariyal Cocos nucifera Fibrous mesocarp – Hard fibre used for coir, rope, mats, carpets. India principal producer (Mainly Kerala).
6. Kenaf/Deccan hemp/Java jute Hibiscus cannabinus (Malvaceae) Fibres from lower part of the stem; used for bags, sacks, cordage, nets, substitute for jute.
7. Ramie/China grass Boehmeria nivea (Urticaceae) Toughest, longest, strongest most durable fibre present in Secondary phloem; used for brush, ropes, carpets, cordage bags, chinese linen.
8. Abaca /Manila hemp Musa textilis (Musaceae) Strongest of all structure fibres. Leaf sheath contains fibres, used for marine cordage, fishing industry.
9. Sisal Agave sisalana (Agavaceae) Leaves contain fibres; used for carpet backing bags, industrial fabrics.
10. Kapok Bombax pentantrum (Bombacaceae) Inner wall of fruit contains fibres; used for stuffing mattresses, pillow, cushions, life belts, life jackets.
11. Red silk cotton Semal Salmalia malabarica Seed hairs, substitute for kapok.
12. Cotton Kapas Gossypium sp. (Malvaceae)
13. Jute Jute Corchorus capsularis,    C. olitorius (Tiliaceae)
14. Broomcorn Sorghum vulgare var. technicum (Poaceae)


Some important Commercial woods

Common Name Hindi name Botanical name and Family Special features
1.Sisso/Indian redwood Sheesham Dalbergia sisso (Papilionaceae) Finest wood for cabinet and furniture, used for railway sleepes, musical instruments, tobacco pipes, and also for charcoal making.
2. Ebony Diospyrous ebenum (Ebenaceae) For decorative work, piano keys, handles of cutlery, chess pieces, walking sticks, flutes etc.
3. Sal Sal Shorea robusta (Dipterocarpaceae) Ranks second to teak; used for construction work, eminently suited for sleepers.
4. Mahogany Swietenia mahagoni (Meliaceae) Light reflecting quality; used for furnitures, aeroplane propellers; ship building.
5. Teak Saguan Tectona grandis (Verbenaceae) Railway carriage, House construction, ships, bridge, Toys, Plywood, Boats etc.; extremely durable and hard.
6. Cedar Deodar Cedrus deodara (Pinaceae) Most strong Indian soft wood, Railway sleepers, doors, windows.
7. Pinewood Chir Pinus roxburghi, Pinus sp. Packing cases, Railway sleepers, Match industry.
8. Birch Bhojpatra Betula alnoides (Betulaceae) Plywood, furniture.
9. Balsa Ochroma pyramidale Lightest commercial wood, used as sandwitch material for gliders, etc.
10. Sandalwood Chandan Santalum album (Santalaceae) Boxes, toys, religious ceremonies.


Some important Resin-yielding Plants

Common name Botanical name Special features
1. Kala damar (a)  Shorea tumbuggaia (Dipterocarpaceae)

(b)  Canarium sirictum (Burseraceae)

Resin from stem; used for incense.


Used in preparing varnishes and medical plasters.

2. White damar Vateria indica (Dipterocarpaceae) Resin from trunk used as an incense, and in paints and varnishes.
3. Lacquer Rhus vernicifera (Anacardiaceae) Applied as varnish.
4. Asafoetida (Hing) Ferula asafoetida (Umbelliferae) Powerful, pungent odour, bitter taste, used in perfumery and as flavouring agent, antihelmintic.
5. Turpentines Pinus roxburghi (Pinaceae) Varnishes, paints etc.


Common beverages

Common name Source Plant and Family Special features
A. Alcoholic Beverages
1. Beer (From barley malt) Hordeum vulgare (Gramineae) Barley malt used; alcohol 3–6%.
2. Brandy (From wine grapes) Vitis vinifera (Vitaceae) Fermented and distilled juice; alcohol content 60–70%.
3. Rum (From molasses, sugar cane juice) Saccharum officinarum (Gramineae) A distilled beverage; alcohol content about 40%.
4. Whisky (From malted or unmalted cereals or potatoes)  — Distilled alcohol, alcohol content about 50%.
B. Non-Alcoholic Beverages
5. Cocoa Theobroma cacao (Sterculiaceae) Seeds used for non-alcoholic beverage; butter from seeds used for making chocolates.
6. Coffee Coffea arabica (Rubiaceae) Dried beans (seeds) roasted, ground and brewed to make stimulating beverage; caffeine is main alkaloid.
7. Tea Camellia sinensis (Theaceae) (=Thea sinensis) Cured leaves used as beverage; it contains 2–5% theine (alkaloid).


Important Spices and Condiments

Common name Hindi name Source Plant and Family Special features
1. Black pepper Kali mirch Piper nigrum (Piperaceae) Fruits used as condiments; also used medicinally as stimulant, carminative and stomachic.
2. Caraway Jeera Carum carvi (Umbelliferae) Fruits used as condiment, medicinally as stomachic and carminative.
3. Cardamomum Chhoti elaichi Elettaria cardamomum (Zingiberaceae) Dried fruits used as condiment, in paan; as flavouring agent; in medicine as stimulant and carminative.
4. Cardamomum Indian Bari elaichi Ammomum aromaticum (zingiberaceae) Seeds used as flavouring agent; seed oil stimulant and stomachic.
5. Cassie Tejpat Cinnamomum tamala (Lauraceae) Dried leaves used as condiment; leaves are carminative and used in colic and diarrhoea.
6. Chillies, Red pepper Mirch, Lal mirch Capsicum annuum (Solanaceae) Fruits green and ripe used as condiment; fruits used as pickle, powerful stimulant and carminative. Good source of vitamin C.
7. Cloves Laung Syzygium aromaticum (Myrtaceae) Dried (unopened) flower buds used as spice; clove bud oil useful in tooth pain; also as clearing agent in biology laboratory.
8. Coriander Dhania Coriandrum sativum (Umbelliferae) Fruits and leaves are used as condiment; used as flavouring agent also.
9. Cinnamon Dalchini Cinnamonum zeylanicum (Lauraceae) (=C. verum) Dried inner bark used for its delicate fragrance and sweet taste.
10. Ginger Adrak Zingiber officinale (Zingiberaceae) Rhizomes used as pice and condiment as well in medicine.
11. Nutmeg Jaiphal Myristica fragrans (Myristicaceae) Nutmeg (kernel) and mace (aril) used as colouring and flavouring agents.
12. Saffron Kesar, Jaffran Crocus sativus (Iridaceae) Stigmas and tops of styles are used as colouring and flavouring agents.
13. Turmeric Haldi Curcuma domestica (Zingiberaceae) Rhizomes used for seasoning of food and as condiment; medicinally used as stomachic, tonic, blood purifier and antiseptic; also used as colouring agent.
14. Fennel Saunf Foeniculum vulgare (Umbelliferae) Used as flavouring agent for soups, confectionaries; fennel oil used in infantile colic, flatulence; good vermicide.
15. Vanilla Vanilla planifolia (Orchidaceae) Characteristic flavour due to vanillin, flavouring agent for ice creams, soft drinks, confectionary.


Some important Fumitories and Masticatiories

Common name Hindi name Source Plant and Family Special features
1. Tobacco Tambakhu Nicotiana tabacum (Solanaceae) Leaves contain nicotine; mild stimulant, causes lung cancer and atherosclerosis of coronoary arteries; accelerates heart beat, increases hypertension and bronchial cough.
2. Kola Cola nitida (Stercuiliaceae) Seeds used as masticatory, contain glycoside kolanin and alkaloid caffeine.
3. Areca nut Supari Areca catechu l Betel nut palm (Palmae) Endosperm of the nut used as masticatory alongwith betal (paan); used as vermifuge for tapeworm in veterinary practice.
4. Betal, Paan Piper betel (Piperaceae) The leaves provide famous paan.
5. Coca Cocain Erythroxylon coca (Erythroxylaceae) Leaves contain cocaine; it is chewed with morphine or heroin called speed ball; acts on central nervous system causing psychic exaltation; reduces apetite; physical and mental deterioration leads to death.
6. Hemp Indian Ganja, Bhang Cannabis sativa (Cannabinaceae) Female flowers used for extraction of hallucinogenic narcotics-hashish, charas, marijuana, bhang, ganja, etc. alter thoughts, feelings and perceptions; causes addiction.
7. Opium Afeem Papaver somniferum (Papaveraceae) Latex from unripe capsules yields alkaloid morphine.

Some important Medicines and their source plants

Common name Hindi name Source Plant & Family Special features
1.Quinine, Cinchona Kunain Cinchona officinalis (Rubiaceae) Bark of trunk is a source of quinine used for treatment of malarial fevers.
2. Wormseed Kirmala Artemisia maritima (Compositae) Flower heads yield santonin used to expel threadworms and roundworms.
3. Withania, Asgand, Punir Ashwagandha Withania somnifera (Solanaceae) Roots used for general weakness and rheumatism, it is diuretic and promotes urination; roots and leaves antibacterial.
4. Belladonna, Night shade Sag-angur Angurshefa Atropa belladonna (Solanaceae) Leaves used as tonic, antispasmodic and sedative, atropine- an alkaloid obtained from leaves is used in eye-testing and treatment.
5. Malabar nut Vasaka Adhatoda vesica (Acanthaceae) Fresh/dried leaves constitute the drug vasaka used in bronchial troubles. Active principle – vascin.
6. Camphor Kapur Cinnamomum camphora (Lauraceae) Wood yields camphor used in inflammations, rheumatic pain and sprains; and internally in diarrhoea; and as cardiac stimulant.
7. Foxglove Tilpushpi Digitalis purpurea (Scrophulariaceae) Dried leaves yield glucoside digitoxin useful for regulating tone and rhythm of heart, used in ointments for application of burns and wounds.
8. Epheda Khanda Ephedra gerardiana (Ephedraceae) Dried stem yields ephedrine useful against asthma, cold, inflamation of mucous membrane; also used as cardiac stimulant and against allergenic rashes.
9. Aconitum; Monks hood Balnag Aconitum napellus (Ranuculaceae) Roots yield the drug `aconite’ used for rheumatism and as nerve sedative externally for rheumatism and internally to relieve pain cough, asthma and fever.
10. Garlic Lahsun Allium sativum (Liliaceae) Used in intestinal disorder, cough, lever, in colitis and dilation of coronary arteries.
11. Ginseng Panax schinseng (Araliaceae) Gingseng root is used as stimulant and stomachic, it reduces high blood pressure and raises low blood pressure.
12. Ipecae Cephaelis ipecacuanha (Rubiaceae) Annulated rhizomes yield cephaeline used as emetic and expectorant, also in treatment  of amoebic dysentery and pyrrhoea.
13.Licorice, Liquorice Mulhatti Glycyrrhiza glabra (Papilionaceae) Glycyrrhizin, a glycoside in root used for treating gastric ulcers, cough and sore throat.
14.Nuxvomica/ Strychnine Kuchla Strychnos nuxvomica (Loganiaceae) Seeds yield a drugh nux-vomica, used in low doses as tonic stimulant and in treatment of paralysis and nervous disorders. Higher doses used for killing stray dogs and pets.
15. Psyllium, lsabgol Plantago ovata  (Plantaginaceae) Tasteless substances in seeds acts as a mild laxative; used in the treatment of dysentery and other disorders of digestive system.
16. Opium Afeem (Afim) Papaver somniferum (Papaveraceae) Milky latex from capsule yields alkaloids especially morphine used to reduce blood pressure, bleeding; to treat diarrhoea vomitting; and in cough medicines.
17. Rauwolfia Sarpagandha Rauwolfia serpentina (Apocynaceae) Roots bark yield alkaloid reserpine-used for treatment of schizophrenia and other mental disorders; widely employed for treating high blood pressure.
18. Ironwood Nagkesar Mesua ferrea (Guttiferae) Flowers used for cough; buds in dysentry.
19. Indian Aloe Gheegwar Aloe vera (Liliaceae) Leaves use in fever, enlargement of liver, Skin disease, Piles, Jaundice.

Some other useful plants

English /Common name Botanical name Family Uses
1. Para rubber Hevea brasiliensis Euphorbiaceae Widely utilized in manufacture of tyres, tubes and other articles, used in sports, medical instruments, agriculture, etc.
2. Indian rubber Ficus elastica Moraceae Used for manufacture of various articles.
3. Chickle Achras sapota Sapotaceae Used in chewing-gum.
4. Babul (Kikar) Acacia nilotica Mimosaceae Gum edible and used in medicines, printing, paints, etc; wood is used as fuel.
5. Catechu  (Kathha) Acacia catechu Mimosoidae Tannin obtained from heart wood and bark used in paan (betal); and for dyeing cloth.
6. Cork oak Quercus suber Fagaceae Cork used as bottle stoppers, soles for shoes, insulating material; for manufacture of linoleum.
7. Henna  (Mehndi) Lawsonia inermis Lythraceae Leaves yield dye used as mehndi
8. Indigo (Nil) Indigofera tinctoria Fabaceae A source of indigo
9. Orchill Rochella tinctoria Lichens Source of orcein stain, used for cytological work.
10.Logwood (Patang) Haematoxylon campechianum Mimosaceae Heartwood yields a dye hematoxylin; used to dye cloth; also useful as nuclear stain in biological laboratories.
11. Sugarcane (Ganna) Saccharum officinarum Poaceae Cane juice is used for preparing gur and jaggery, sugar, etc; baggase used as fuel and in the manufacture of paper.
12.Beet root (Chukandar) Beta vulgaris Chenopodiaceae Roots are source of sugar; tops and pulps are used as stock feed.
13. Neem tree Azadirechta indica Meliaceae The fresh Juice of the leaves is given for the treatment of intestinal worms with honey the Juice is used for Jaundice and skin diseases. Its leaves are used as an antiseptic.
14. Tulsi Ocimum sanctum Labiatae The leaves are aromatic their decoction is given in malaria gastric diseases of children check vomiting.
15. Ammi (Azwain) Trachyspermum ammi Apiaceae It is used in gastric trouble bronchitis, as purgative etc.
16. Chembalic Myrobalan (Harra) Terminalia chebula Combrtaceae As a constituent of ‘Trifla’.


Some important Legumes

English name / Common name Botanical name Family
1. Black gram (Urd) Phaseolus mungo = Vigna mungo Fabaceae (Papilionaceae)
2. Cajan, Pigeon pea (Arhar) Cajanus cajan Fabaceae
3. Cow pea (Lobia) Vigna unguiculata = V. sinensis Fabaceae
4. Gram, Chick pea (Chana) Cicer arietinum Fabaceae
5. Green gram (Moong) Phaseolus aureus = Vigna radiata Fabaceae
6. Lentil (Masoor) Lens esculenta Fabaceae
7. Pea (Matar) Pisum sativum Fabaceae
8. Soyabean (Soyabean) Glycine max Fabaceae
9. French bean Phaseolus vulgaris Fabaceae
10. Moth bean Phaseolus aconitifolius Fabaceae
11. Cluster bean Cyamopsis tetrogonoloba Fabaceae

Some Fibre yielding plants

English name / Common name Botanical name Family
1. Cotton  (Kapas) Gossypium sp. Malvaceae
2. Flax (Alsi) Linum usitatissimum Linaceae
3. Jute Corchorus capsularis, C. olitorius Tiliaceae
4. Coir (Nariyal) Cocos nucifera Arecaceae
5. Broomcorn Sorghum vulgare var. technicum Poaceae
6. Kapok Ceiba pentandra Bombacaceae
7. Sunn hemp Crotolaria juncea Fabaceae
8. Hemp (Bhang) Cannabis sativa Cannabinaceae
9. Munj Saccharum munja Poaceae
10. Ramie Boehmeria nivea Urticaceae
11. Manila hemp (Abaca) Musa textiles Musaceae


Some important Essential oils and Fatty oils

English name / Common name Botanical name Family
(A) Essential oils (Volatile oils)    
1. Jasmine (Juhi) Jasminum auriculatum Oleaceae
2. Khas Khas (Vetiver) Vetiveria zizunoides Poaceae
3. Lavender Lavandula officinalis Lamiaceae
4. Rose (Gulab) Rosa damascena Rosaceae
5. Sandalwood (Chandan) Santalum album Santalaceae
6. Geranium Pelargonium graveolens Lamiaceae
(B) Fatty oils (Non-volatile oils)  
7. Coconut (Nariyal) Cocos nucifera Arecaceae (Palmae)
8. Mustard (Sarson) Brassica campestris var. sarson Brassicaceae
9. Ground nut (Moonghphali) Arachis hypogaea Fabaceae
10. Safflower (Kusum) Carthamus tinctorius Asteraceae
11. Sesame (Til) Sesamum indicum Pedaliaceae
12. Soyabean Glycine max Fabaceae
13. Sunflower (Surajmukhi) Helianthus annuus Asteraceae
14. Castor (Arandi) Ricinus communis Euphorbiaceae


(7) Petroleum and Oil producing plant : Melvin Calvin was first to identify few petroleum plants – the plants whose products can be used in place of petrol and oil. Most of such plants belong to families Asclepiadaceae, Euphorbiaceae and Apocynaceae. These plants are able to convert a subtantial amount of hydrocarbons into latex. Euphorbia lathyrus contains a mixture like terpen which can be converted into gasoline. Oil is also extracted from Xanthagnum.

 Food preservation.

In various seasons we have different varieties of vegetables, fruits, fish and meet. Their availability can be ensured through out the year only by preserving them. More over human diet includes a wide variety of substance which are rich in nutrients, thus serve as excellent media for microbial growth. Metabolic activities of micro organisms alter the condition of food resulting in ‘spoilage’. Proteins are spoiled by Pseudomonas proteus. Carbohydrate foods are degraded by yeasts, Streptococcus. Fats are digested mainly by moulds. Therefore to protect food products from rotting, preservation is necessary. It has been estimated that every year about 30% of the total production of vegetables and fruits in India are perished due to lack of knowledge of food–preservation among the farmers. ‘Preservation’ not only makes food to remain fresh for a long time and makes storage possible, but it also provides employment to people and obtain a proper cost for the food products.

(1) Methods of food-preservation : Preservation is the technique used to protect food products for a longer duration, retaining its nutritive value as much as possible. The methods of food preservation used in food processing and food-preservation industries are canning & bottling, preparing jam, jelly, pickle, sauce and ketchups. The methods of food-preservation is generally of two types :

(i) Temporary food-preservation : This includes some simple methods by which food materials can be kept for a much longer time than usual but not for an indefinite period. Following are few important methods of temporary food preservation.

(a) Pasteurization : This method was devised by Louis Pasteur (1822-95). It is now been used as a temporary milk preservation method. In this method milk is heated in large tank at 62.9oC for 30 minutes and then cooled rapidly. This minimizes the population of bacteria, responsible for souring milk.

(b) Low temperature storage : By this method meet, fish, vegetables, fruits and milk products can be preserved. Two methods are employed in the preservation of food by cold temperature.

  • Chilling : The temperature is kept just above the freezing point, e.g., preservation of butter, cheese.
  • Freezing : Temperature around –25oC is maintained. e.g., preservation of mushrooms, meat etc.

(c) Exclusion of air : Air is one of the source of micro organisms and by avoiding content with air, food-materials can be preserved longer air tight containess are used for this purpose.

(d) Exclusion of moisture : Presence of moisture and warmth is conducive for the growth of micro–organisms. Therefore dehydrated food-materials should be packed in moisture proof and air tight containers and polythene bags. Drying of food is necessary before its packing. Fruits and vegetables are dehydrated by three means i.e. by sun drying, oven drying and mechanical drying. Mushrooms are first immersed in boiling water for 3 minutes and immediately dipped in cold water to destroy enzymes (The process is called ‘Blomching’) and then subjected to pass through warm air through warm air before packing is done.

(e) Asepsis : It means avoidence or exclusion of micro organisms. Food material is not brought in contact with microbes. For this some disinfectant like Ca(OH)2 solution are used or a mixture of 85% carbondioxide & 15% ethylene is fumigated.

(f) Use of chemicals : Some chemicals like Potasium Metabisulphite and Sodium Benzoate inhibits the growth of micro organisms.

(g) Steam under pressure : Use of ‘Pressure cooker’ is the most effective method of ‘high temperature food preservation’ since it can kill all vegetative cells and spores.

(ii) Permanent food preservation : In this method food inhabiting micro organisms are totally destroyed so that the food can be stored for an indefinite period. Following methods are used for permanent food preservation.

(a) Dehydration : When percentage of water is reduced ‘Total soluble salt’ (T.S.S.) increases and conditions become unfavourable for micro organism to grow. There are two means by which drying of fruits and vegetables can be done by :

  • Sun drying : Food stuff is kept in sun for several days by spreading it evenly on a tray.
  • Over drying : Food stuff is first kept in a hot over at 145o F for 5 minutes and then taken out and cooled under a fan for 15 minutes. This method is repeated several times.

(b) Heat sterilization : Food stuff is first packed in an air tight container and this packed material is subjected to high temperature (212oF) in a pressure cooker.

(c) Osmotic pressure method : This is based on the principle of plasmolysing and thus arresting the metabolism of a cell. Water is withdrawn from the cells of micro organisms and they get plasmolysed when come in contact with a concentrated solution of sugar, salt, oil.

‘Squash’ contains, fruit juice (33%) and 55% sugar. ‘Jam’ which obtained from pulp of fruit and ‘Jelly’ which is made up of a mixture of fruits juice and pectin contain 66% sugar. In preserving vegetables and fruits as pickles, addition of 18% salt is essential. Sauce (containing 15% solid matter) and ketchup (containing 95% solid matter) also cntain salt, sugar and vinegar as preservatives.

(d) Use of Vinegar : Vinegar is chemically acetic acid and makes the medium acidic, reduces pH and checks bacterial growth thus providing food preservation. Used in pickles, sauce, chatni as preservative.

(e) Antibiotics : ‘Chlorotetracyclin’ (CTC) antibiotic is used in poultry and other non-vegetarian products. Besides few antibiotics as terramycin, subtilin and tylosin are also used as food preservatives.

(f) Radiation : High energy rays like –rays are used to destroy micro organisms present in food material. Gamma rays and ultraviolet rays have been used more often for this purpose.

(g) Fermentation : Food containing carbohydrate is subjected to fermentation as a result of which alcohol and vinegar are produced.

 Origin of agriculture.

  • After the evolution of man and from the time of his origin, he has been basically a hunter of animals and gatherer of plant products for his food. He lived in small groups, following a nomadic way of life.
  • The earliest human civilizations around the river Nile in Egypt, the Chinese river valleys and the northern Indian plains are linked with crop cultivation.
  • Evidences indicate that agriculture originated independently in south-east Asia, south west Asia, African and American continents. Food gathering in south west Asia began in 10,000 B.C. whereas food production in 9000 B.C. Then food production spread to eastern Europe and the remaining part of the continent.
  • The old stone age or paleolithic period was characterized by the absence of agriculture. Mesolithic period represented a transition period when scanty agriculture began here and there and lasted several thousand years.
  • Neolithic or New stone age was fully developed by 3000 B.C. where in agriculture was well developed.
  • Carl Saver has pointed out that first plants that grew wild and then cultivated, were nitrogen loving and multipurpose plants.
  • The plants cultivated early in the development of agriculture were, hemp (Cannabis sativa) and baobab tree (Adansonia digitate) in Africa, mulberry tree (Morus alba) in china and coconut palm (Cocos nucifera) in tropical areas such as Mexico and coastal areas in India.
  • In South Africa, the individuals of Kung tribe depend on two plants for their survival. These are mongongo nut (Reicinidendron rautanenii) and marama bean (Bauhinia esculenta).
  • Another multipurpose plant of tropical areas is coconut palm (Cocos nucifera) Which is Knows as “mans most useful tree” and in India it is known as “Kalpa vriksha ” or “Tree of heaven”.

(1) Centre of Origin : Nikolai Ivanovitch Vavilov (1926) proposed different centres of origin for various crop plants on two criteria :

(i) Occurrence of wild relatives      (ii) Occurrence of maximum variation in the crop

Out of his 11 centres 10 are given below :

(i) South East Asia : Rice, Pigeon pea, Banana, Mango, Orange, Brinjal, Black pepper, Sugarcane.

(ii) China : Onion, Tea, Soyabean.

(iii) South West Asia : Wheat.

(iv) Asia minor and Afghanistan : Rye lentil, Apple, Pear, Apricot, Pomegranate, Pistachio, Almond.

(v) Mediterranean : Oat, Lettuce, Cabbage, Beet.

(vi) Ethiopia : Barley, Sorghum, Coffee.

(vii) Brazil : Groundnut, Pineapple, Rubber.

(viii) Peruvian Andes (South America) : Potato, Tomato, Chilli.

(ix) Mexico and Central America : Maize and Cotton.

(x) U.S.A. : Sunflower.

Important plants of new world are Maize, Potato, Tomato, Sunflower, Groundnut, Red pepper, Pineapple, Guava, Sapota Coco.

  • Natural home : Place of origin of a cultivated crop.
  • Secondary Home : The major centre of production of a crop where wild relatives do not occur and which is faraway from the center of origin or natural home.
  • Green Revolution : It is rapid increase in agricultural out-put as witnessed  in India during 1970s. It has been achieved through introduction of high yielding varieties increased irrigation facilities, fertilizer application, weed pest and pathogen control, multiple cropping and  better agricultural management .
  • FAO : Food and Agricultural Organisation of U.N.O.
  • IRRI : International Rice Research Institute, Los Banos, Philippines.
  • ICRISAT : International Crops Research Institute for Semi Arid Tropics, Hyderabad, India.

(2) Additional resources of food in future

(i) Phytoplanktons (Sea kelps and some red algae) are utilized as food by man.

(ii) A green algae, Chlorella, and a fungus Saccharomyces (yeast) have protein content 70% and can be potential sources for future protein.

 Plant breeding.

The development of new variety of plants possessing desirable characters from the existing ones is called plant Breeding. The crop improvement depends upon favourable environment (Good irrigation, better fertilizers and precautions to avoid losses due to disease)  together with superior hereditary characters.

  • Swaminathan : Father of plant breeding in India.
  • Thomas Fairchild (1717) produced first hybrid plant artificially.
  • Cotton Mather (1761) recognised the process of natural selection in maize.
  • Joseph Kolreuter (1760-66) produced many hybrids in tobacco.
  • Methods of plant breeding

(1) Plant introduction                  (2) Selection                   (3) Hybridization                       (4) Mutation

(5) Polyploidy                             (6) Tissue culture                    (7) Genetic engineering

(1) Plant introduction

(i) Plant introduction means introducing a plant having desirable characters (e.g., high yield, disease resistance and vigorous growth) form a region or a country where it grows naturally to region or a country where it did not occur earlier.

(ii) If brought from foreign country, it is called Exotic Collection (EC) but it brought from same country, then it is called Indigenous Collection (IC).

(iii) Introduced plants may be used directly for cultivation (Primary introduction) or may be used after subjecting to selection/ hybridization (Secondary introduction).

(iv) Acclimatisation : The adjustment of newly introduced plant to new or changed environment is called Acclimatisation.

(v) Introduced plant materials are subjected to “plant protection and quarantine regulations” to check the entry of Pathogens.

(vi) New plants are usually introduced in the form of cuttings or seeds.

(vii) Portugese traders and East India Company were foreign agencies which introduced many plants in India.

National Bureau of Plant Genetic Resources, Delhi (Estd., 1976) helps in plant introduction in India.

(2) Selection : It is the picking up of plant having desirable characters (e.g., high yield, disease resistant and vigorous growth) from a given pupulation of plants based on its phenotypic characters. This involves preserving of favorable characters and gradual elimination of undesirable ones.

(i) Methods of selection : (a) Mass selection          (b) Pure line selection      (c) Clonal selection

(a) Mass selection : It is practised in naturally cross-pollinated crops e.g., Maize. The first step involves selection of plants, having  desirable characters from a given population of plants, based on phenotypic characters. The seeds of selected plants are then mixed and sown in the same field (Mixed cropping) to allow natural cross pollination. The plants are selected from this field by eliminating the undesirable ones and saving the best. The seeds of selected plants are multiplied in large numbers and supplied to the farmers.

  • Advantage
  • It is the simplest, easiest and quickest method of crop improvement.
  • It is only method for improving the wild or local varieties to meet the immediate needs of farmers.

(b) Pure line selection : It is practised in natural self – pollinated crops e.g., Wheat.

First step involves selection of few plants each having one or more desirable characters from a genetically mixed population. Each of these selected plant is then selfed through several generation to attain homozygosity for the selected characters. The homozygous plants are then multiplied. A Population of homozygous plants raised from a single homozygous plant is called pure line. The pure lines are now crossed to introduce several desirable characters in to a single synthetic one which is then multiplied and supplied to the farmers for cultivation.

  • Advantage : In pure line selection the selected plants retain their desirable characters for several years.
  • Disadvantage
  • No new genotype are created by pure line selection.
  • It requires 10 – 12 years for raising the desired variety.

(c) Clonal Selection : It is practised in vegetatively  propagated plants e.g., Sugarcane, Banana, Potato, Onion, Turnip etc.

  • Definition : Clonal selection is the method of selection of desirable clones from the mixed population of vegetatively propagated crops. All the progenies of a single plant obtained vegetatively are known as clone.
  • Procedure : The first step is selection of a plant from a population of a crop based on phenotypic characters. The plant is then multiplied vegetatively and supplied to the farmers for cultivation.
  • Advantage
  • Varieties are stable and easy to maintain.
  • Hybrid vigour is easily utilized.
  • Only methods to improve the clonal crops.
  • Limitations
  • Only applicable to vegetatively propagated crops.
  • Creats no new variation.

(3) Hybridization : It is the method of producing new crop varieties in which two or more plants of unlike genetical constitution are crossed together. The plants which are crossed together may belong to the same species different species or different genera. According to this relationship between parental plants, the hybridization is divided into following categories :

(i) Intravarietal hybridization : The crosses are made between the plants of same variety.

(ii) Intervarietal hybridization : The crosses are made between the plants belonging to two different varieties of the same species and is also known as intraspecific hybridization.

(iii) Interspecific hybridization : The plants of two different species belonging to the same genus are crossed together. It is also known as intergeneric hybridization.

(iv) Intergeneric hybridization : The crosses are made between the plant belonging to two different genera.

(v) Introgressive hybridization : In this type of hybridization one species is completely replaced by another in nature.

(a) Procedure

  • Selection of parents : The first step in hybridization is to select the plants which are to be used as parents and can supply all the desired important characters which lack in a good standard variety.
  • Selfing of parents : This is the second step consisting in artificial self pollination of parents. It is very essential for eliminating the undesirable characters and obtaining inbreeds.

The selected inbreds, before utilization, are tested for combining ability, both specific and general and the most suitable ones are further utilized in the hybridization technique.

(b) Hybridization Technique

  • The inbreeds are grown under normal and protected conditions in the isolated plots so that they may develop properly and get full shelter against insects, pests, animals, birds and diseases.
  • They are sown at different dates to secure simultaneous flowering. The males and females to be crossed are marked in such a way that the dehiscence of anthers coincides the stigma receptivity. They are then carried out under the following operations :
  • Emasculation : “The removal of stamens from female parent before they burst and have shed their pollens”.
  • Bagging : To avoid contamination by unwanted pollen, the female and male flowers are covered with cellophane or parchment or paper bags. This process is called bagging.
  • Crossing : “The artificial cross – pollination between the genetically unlike plants” and after that the female cross pollinated flower is again bagged.
  • Labelling : The crossed flowers are properly tagged and labelled.

(c) Harvesting hybrid seeds and raising F1 generation : The bags are removed and the crossed heads of desirable characters are harvested and collected with their attached labels separately in envelopes. After complete drying, they are threshed individually and preserved as such.

In coming season, these seeds are sown separately to raise the F1 generation. The plants of F1 generation are progenies of crossed seeds and called hybrids.

(d) Hybridization Methods : Handling of F1 and subsequent generations by different selection methods of hybridization which are different for self and cross-pollinated crops.

  • Self pollinated crops : (i) Pedigree method (ii) Bulk method  (iii) Back cross method.
  • Cross pollinated crops : (i) Single cross (AxB) (ii) Three cross (AxB) x C.
  • Heterosis or Hybrid vigour : Heterosis or hybrid vigour is the increased vigour growth yield or function of a hybrid over the parents, resulting from the crossing of genetically unlike organisms. Heterosis word used by scientist Shull. The heterosis normally involves two steps :
  • The plants are selected for certain desirable characters and are selfed repeatedly through several generations to get pure lines for different characters.
  • The pure lines for different desirable characters are crossed to get the heterotic effect in the hybrids.

(4) Mutation : Sudden heritable changes in an organism other than those due to mandelian segregation and recombination is called mutation.

(i) Procedure of mutation breeding

(a) Plant material for irradiation : The plant can be treated in any form i.e. seeds, seedling, shoots and grafts. Seed-short wave length radiations like UV, X-ray, cosmic rays, ionising radiations like gamma rays emitting from radio-active istopes like cobalt 60 calcium 137, chemicals like nitrous oxide, ethylmethane sulphonate (EMS), carbon tatra sulphide, nitromethyl and nitroethyl urea are some of the sources utilised to induce mutation. Many types of wheat like Sharbati, Sonora and Pusa lerma are amber coloured grain mutants of red varieties like Sonora 64 and Lerma Roja – 64.

(ii) Limitations of mutations breeding

(a) Most induced mutation are undesirable. Some of which result in death of the organism.

(b) The rates of mutations are very low and large number of plants are employed to select a certain desirable mutant.

(c) Most mutations are not stable and get reverted.

(d) Since mutations are recessive they are expressed only in recessive homozygous condition otherwise they remain undetected.

(e) In sexually reproducing plants mutations are expressed and inherited only if they occur in gametes.

(5) Polyploidy : An organism with the number of sets of chromosomes higher that the diploids are termed polyploids and this process called polyploidy. It is of two types :

(i) Autopolyploidy : If polyploidy arises within a species. It is called autopolyploidy.

(ii) Allopolyploids : If the number of sets of chromosomes gets increase in a heterozygous (breeding between two different species) this is referreds as allopolyploids.

Polyploidy arises either due to fusing of one egg with two sperm or vice versa; or by failure of mitosis in somatic cells where chromosomes have duplicated in S- phase of interphase. Artificially polyploidy can be induced by using colchicine.

  • Triploid condition arises by crossing a tetraploid (4n) and a diploid (2n) plant e.g., Sugarbeets, apple, pear, guava, banana, water melon, pea, etc.
  • They are more vigorous and they have higher yield.
  • Triploids exhibit a large degree of sexual sterility and have therefore to be propagated mostly by vegetative means.
  • The polyploids which possess an exact multiple of the haploid set of chromosomes are called “euploids”.
  • Some polyploids where numerical change in chromosome number of individuals is not the exact multiple of haploid genome, which are called Aneuploids”.
  • Example : Back cross between hybrids of Saccharum officinarum X spontaneum with either S. spontaneum or S. officinarum.

Some major crop species of presumed polyploid origin

S.No. Common name Scentific name Apparent base number Present diploid number and ploidy level
(1) Wheat Triticum 2n = 28, tetraploid
(a) Durum T. turgidum 2n = 28, tetraploid
(b) Club T. aestivum 2n = 42, hexaploid
(2) Sugarcane Saccharum officinarum (Poaceae) 2n = 80, octaploid
(3) Tobacco Nicotiana tabacum (Solanaceae) 2n = 48, tetraploid
(4) Coffee Coffea arabica (Rubiaceae) 2n = 44, tetraploid
(5) Cotton Gossypium hirsutum (Malvaceae) 2n = 52, tetraploid
(6) Potato Solanum tuberosum (Solanaceae) 2n = 48, tetraploid
(7) Strawberry Fragaria ananassa (Rosaceae) 2n = 56, octaploid


(6) Tissue culture : Tissue culture requires separation of cells, tissues or organs of a plant and allowing them to grow in aseptic nutrient media under controlled light and temperature. The cultured parts termed explants, require energy (Usually a carbohydrate like sucrose) and salts (Both macro and micro nutrients) apart from vitamins and the amino acid glycine. When a tissue from an organ is cultured, It grows into undifferentiated tissue called “callus”. The callus can be differentiated in to shoot, root or complete plants by manipulating the concentration of Auxin and cytokinin. The advantages of tissue culture in the improvement of crop plants are :

(i) Micropropagation : Production of large number of individuals in vitro in a limited space which can be employed for  agriculture, horticulture and forestry. e.g., Potato, Bananas, Begonia, Carnation, Chrysanthemum and Gerbera.

(ii) Somatic embryogenesis : Somatic cells are cultured in electric shakers to obtain single cell suspension. When the number of cells has increased to a maximum depending upon the amount of medium, the culture is made stationary. Each cell starts differentiating in to an independent embryo showing all the stages of embryo development such as globular heart shaped and torpedo shaped stages. They are called “embryoids”. Somatic embryoids can give rise a complete plant having normal root system. Success has been achieved in carrot, celery and alfalfa.

(iii) Raising of disease free plants : The virus free clones can be obtained from a virus infected plant by tissue culture since virus is translocated through sieve tubes, the apical meristem of virus infected plant remain free of virus. The shoot apex of such plant can be cultured.

(iv) Androgenic haploids : These are haploid plants raised form pollen grains by another culture technique. The first example of androgenic haploid was reported by Guha and Maheshwari (1964) from anther culture of Datura innoxia.

(v) Rescue of hybrid embryos : The hybrid embryos produced as result of interspecific or intergeneric crosses normally collapse due to incompatibility. These embryos can be isolated from female plants and rescued by growing on synthetic medium.

(vi) Induction and selection of desirable mutants : The single cell cultures raised in  electric shakers are allowed to grow in static cultures where the cells divide to form colonies. These cells are treated with chemical or physical mutagens to induce mutations. The desirable mutants are selected and multiplied.

(vii) Somaclonal variations : The spontaneous variations which appear in cells or tissues in artificial medium are known as somaclonal variations. The variants having desirable traits such as tolerance to pests, pesticides, diseases and environmental stresses are selected and exploited for agricultural purpose.

(viii) Somatic hybridization : This involves the fusion of  two protoplasts isolated from two different species or genera. The cellulosic cell wall and middle lamella (pectinaceous) are dissolved by making use of the enzyme pectinase and cellulase. The protoplasts can be isolated from leaves, callus from single cell cultures and are then grown on solid medium containing balanced nutrients. e.g., Bromato (cross between brinjal and tomato).

(7) Genetic engineering : Genetic engineering aims at adding, removing or repairing a part of the genetic material (DNA). This is achieved by changing the phenotype according to will :

(i) Transformation                  (ii) Transduction                (iii) Plasmids transfer

These are the three processes by which genotype of an individual can be changed artificially.

  • Prospects of genetic engineering
  • Genetic engineering has put us in a threshold of a new form of medicine, “gene therapy” to find cures for crippling diseases like haemophilia and phenylketonuria.
  • Introduction of genes coding for vitamins, harmones etc., in higher animals opens up new vistas.
  • Possibility of transfer of nitrogen fixing genes from bacteria or blue green algae to major food crops is bound to enhance food production.
  • Production of new plants and animals tailored to new characteristics is now a reality.
  • Through study of the nature and functions of the heredity material is possible because of their technique leading to location of specific genes with in the chromosomes and a deeper insight with in to when and where enzymes are made.
  • Methods
  • Isolation of desired genetic material.
  • Extraction and purification of DNA.
  • DNA multiplied by use of replicating enzymes.
  • Transfer of DNA from one organism to another organism.


Biotechnology is the utilisation of living organisms (or of substances obtained from them) in industrial processes. The organisms involved in biotechnology range from complex organisms like cattle to simple unicellular yeast.

(1) Manufacture of cheese : In old days, cheese was prepared by using the enzyme “rennet” from the lining of stomach of sheep and goat. In 1874 Christian Hansen, a Danish chemist extracted rennet from calf’s stomach and used it for commercial production of cheese.

It is made by separating casein and fat of milk form the liquid. About 400 kinds of cheese are known which can be made from many types of milk (goats, cows, buffaloes or camels) by employing microbes under favourable conditions.

(i) Two types of cheese

(a) Unripended cheese

(b) Ripened cheese (hard cheese ripened internally and soft cheese ripened from out side).

(ii) Manufacture of cheese involves the following steps

(a) Milk is inoculated with a starter culture of bacteria (Streptocooccus lactis or S. cremoris) and warmed at 38°C. If higher temperatures (50°C or more) are used, the starter culture consists of S. Thermophilus combined with Lactobacillus lactis, L. bulgaricus or L. helveticus.

(b) When a certain acidity is reached by the activity of the bacteria, rennet extract obtained from calf stomach is added curdling of milk occurs within one half to half an hour.

(c) The curd is removed and the liquid which separates out is called ” whey”. Whey contain 93% water, 5% lactose mineral and some other substances and is used for the manufacture of lactic acid if cheese is used at this unripened stage, it is called cottage cheese.

(d) The salt is applied to cottage cheese and it is put in to frames and pressed so as to allow continual removal of whey. Salt hastens the removal of moisture and prevents the growth of undesirable microbes. The frames are removed as soon as the cheese has set sufficiently to maintain its shape.

(e) To produce cheese of a desired flavor, it is ripened by employing different bacteria or fungi at a required low temperature and humidity.  The ripening period varies from 1-16 months. Cheese is very nutritious because it contains about 20-30% fat, 20-35% proteins and a small amount of minerals and vitamins. Nearly 400 varities of cheese are available which can be classified in to the categories listed below :


Type of Cheese
Micro organisms used
(A) Camembert Penicillium camemberti, Brevibacterium Ripend by action of microorganisms on the surface of curd
(B) Limburger Streptococcus liquifaciens, Brevibacterium
(A) Roquefort Penicillium roqueforti Combination of surface and interior
(B) Blue


(2) Antibiotics : Antibiotics are substances, primarily produced by certain harmless micro-organisms which in low concentrations are antagonistic to the growth of other micro-organisms such as pathogenic bacteria. The term antibiotic was coined by Selman Waksman in 1942. The property of antibiotics to kill pathogenic micro-organisms is called autobiosis. Chemo-therapeutic value of penicillin was first reported by Florey (1939). Antibiotics are of 2 types :

(i) Broad spectrum antibiotics : Which have a capacity to destroy several pathogenic species of micro-organisms.

(ii) Specific antibiotics : Which have a limited action on a few similar type of pathogens.

  • Biosynthesis of somatostatin : This hormone is secreted from front lobe of pitutary gland. It is made up of 191 amino acid units. Ross isolated first this hormone. The individual suffers dwarfness due to its deficiency. The gene or DNA of this hormone is introduced in coli, near the gene which codes for b-galactosidase.
  • Biosynthesis of insulin : It is a proteinaceons hormone secreted by b-cells of islets of Langerhans of pancreas. In 1916, sharpy-shafer suggested that diabetics occurs due to failure of some islands of pancreas to secrete insulin. In 1921, Aanting and best isolated insulin from pancreas of a dog and showed its efficiency in curing diabetes in human beings. Later on insulin was extracted from pancreas of slaughtered pigs and cottles. Human insulin is formed of 51 amino acids arranged in two polypeptide chains. In 1983 an American company produced first genetically engineered insulin called humulin with the help of coli.

(3) Yeast and Alcohol : Yeasts (Saccharomyces cerevisiae) are single celled fungal organisms. Role of yeast in the production of alcohol, beer, and butter milk was first reported by Louis Pasteur. The process by which the yeasts help in production of alcohol, beer, wine and making of bread, dosa and idli is called fermentation.

(i) Types of yeasts

(a) Baker’s yeast : These include the selected strains of Saccharomyces cerevisiae and Torulopsis utilis. Grown on molasses. These are used to flavour the food, as nutrient ingredients, to ferment and raise dough in bread making (leavening agent).

(b) Brewer’s yeast : Brewing industry produces alcoholic beverages of several types depending upon the fermenting agent and the medium. Fermenting agents are Saccharomyces cerevisiae, S. sake, S. ellipsoidens (wine yeast) and S. pireformis (ginger yeast). Molasses is dark coloured syrup left after extraction of sugar. It still contains 30% sucrose and about 32% invert sugar (mixture of glucose and fructose).

(ii) Industrial production of alcohol : Living yeast cells are immobilized in calcium alginate beads. The beads with living cells are placed in the nutrient medium in the fermentation tank. CO2 is a bi-product of alcohol fermentation. It is collected separately. The medium with fermented product contains yeast cells. Yeast cells are isolated. A part of yeast is kept for further inoculation. The remaining part of the yeast is washed, dried and employed as animal feed.

(4) Vitamins : Term vitamin was given by Funk (1912). Vitamins are organic compounds, generally taken in small amounts along with food and regulate various metabolic activities of body. First vitamin to be isolated was B1(by Funk). Vitamin C was the first vitamin to be produced during fermentation by Albert Gyorgy. Vitamin A and vitamin D were isolated by Mc. Collum and Mellan, respectively.

(i) Riboflavin (Vitamin B2) : Produced in 1938, Fungi (Ashbya gosypi) and Yeast (Eremothecium ashbyii) are the main source.

(ii) Cobalamine (Vitamin B12) : Isolated in 1948 from liver extract. It is obtained from the substances rich in cobalt by the action of Propiobacterium grendenreichii, Bacillus megatherium and Streptomyces olivaceous.

(iii) Ascorbic acid (Vitamin C) : The precursor of ascorbic acid is L-sorbose which is produced from dehydrogenation of D-sorbitol using Acetobacter suboxydans.

(5) Dextrins : These are soluble polysaccharides formed by simple sugars through the agency of micro-organisms like Leuconostoc mesenteroides or its enzyme called dextran sucrose. Fermentation is allowed to proceed till dextrins are obtained. Dextrans represent the 6-10% solution of dextrins. Dextrans are plasma substitutes and are given during shock, haemorrhage, dehydration, etc.

(6) Vaccines : Vaccines contain dead or attenuated (live but weak) pathogens or its antigens. When a vaccine is injected into a healthy person, it provides temporary or permanent immunity to a particular disease. This method of protective inoculation is called vaccination. It was first introduced by Edward Jenner (1790). Louis Pasteur (1879) discovered cholera vaccine. Vaccines produced by conventional techniques are called first generation vaccines. Second generation vaccines have been produced by genetic engineering e.g. against hepatitis B-virus that is causative agent of liver cancer and jaundice. Synthesized vaccines are called third generation vaccines. In India, National Institute of Immunology, New Delhi is involved in the production of antifertility vaccines and kits to detect pregnancy and infectious diseases like amoebiasis, leprosy, hepatitis etc.

(7) Organic acids : Microbes are useful in the manufacture of a number of organic acids.

(i) Acetic acid : It is most important acid being produced by the fermentation of carbohydrates. It is used in phormaceuticals, colouring agents, insecticides and plastics.

(ii) Lactic acid : It was the first organic acid to be produced from microbial fermentation of lactose (milk sugar). Fermenting agents are bacteria, e.g, Streptococcus lactis and Lactobacillus and Fungi, e.g., Rhizopus. Lactic acid is used in confectionery, fruit juices, essence, pickles, canned vegetables and fish products.

(iii) Citric acid : It is obtained by the fermentation of sugar syrup by Aspergillus niger and Mucor species. It is used in dyeing, engraving, medicines, flavouring and preservation of food and candies.

(iv) Gluconic acid : It is prepared by the activity of Aspergillus niger and Penicillium. It is used in preparation of pharmaceuticals. It also acts as a source of Ca++ in infants cows and lactating mothers.

(8) Steroids : Steroids are fatty compounds of high molecular weight which have one 5 carbon and three 6 carbon rings. Biologically important steroids are cholesterol, testosterone, oesterogens, progesterone, cortisterone, cortisone etc. Murrey and Patterson (1950) reported the role of Rhizopus stolonifer to bring about hydroxylation required for steroid synthesis.            Steroids are used to treat individuals with hormonal imbalances. Diosgenin derived from dioscorea has antiinfertility property.

(9) Enzymes : Enzymes are proteinaceons substances of biological origin which catalyse specific biochemical reactions without themselves undergoing any change. The term enzyme was coined by William Kuhne (1867) from the yeast. Buchner (1897) found that living cells of yeast are not required for alcoholic fermentation, but their extract also causes fermentation. In dialysis process, which is used to remove small molecules from enzymes.

(i) Enzymes obtained by microbial activity

(a) Rennet : In 1874, a Danish chemist Christian Hansen, provided the first relatively pure enzyme rennin from calf’s stomach.

(b) Amylase : These degrade starch. These are obtained from bacteria like Bacillus subtilis, B. macerans, B. polymyxa and Fungi like Aspergillus niger and Rhizopus oryzae.

(c) Proteases : It is extracted from Mortierella renispora and Aspergillus. They degrade proteins and polypeptides.

(d) Lipase : Used in making cheese from pasteurized milk obtained from Candida lipolytica. Also lactases, penicillase and sucrose are obtained  from microbial activity.

(ii) Role of enzyme in medicine

(a) TPA (Tissue plasminogen activator) enzyme : It is used to dissolved blood clots in people suffering from heart disorders.

(b) Protein modifying enzymes : Some enzymes are known to modify proteins for human used e.g., conversion of pig insulin into human insulin and called Pseumcelin.

(10) Monoclonal antibodies : The monoclonal antibodies are pure, high affinity, antigen specific proteinaceons bodies developed outside the body from clonal cultures of hybrid cells called “Hybridomas”. These were first discovered by George Kohler and Cesar Milstein (1974). Who proposed that normal antibody producing cells can be used to fuse and inhibit cells from cancerous tumours and called “Myelomas”.

(11) Yoghurt : For the production of yogurt. Pasteurized milk is inoculated with a mixture of Steptococcus thermophilis and Lactobacillus vulgaricus and fermented at 40oC. Curdling of milk is done by lactic acid. From this semi-solid curd. Yoghurt is extracted. America produces 75 Lack kg of yoghurt yearly.

Antibiotic produced by micro-organisms



Microbial source Action Discovery









Chlorotetracycline (Aureomycin)


Oxytetracycline (Terramycin)

Tetracycline (Archromycin)


Dimethyl chlorotetracycline













Vancomycin (Ristocetin)

Novobiocin (Cathomycin)




Polymyxin A,B,C & D






Actinomycin C & D




Penicillin notatum and P. chrysogenum


Streptomyces griseus



S. Venezuelae



S. aureofaciens


S. rimosus


S. taxas (soil)


S.aureofaciens’s mutant



S. erythraeus


S. halstedii

S. ambofaciens



S. noursei

Penicillium griseofulvin


S. Pimprei


S. Orientalis


S. Spheroides


Bacillus bravis


S. Polymyxa


Streptomyces fradiae

S. puniceus

S. decaris

S. orchidacens

S. fragilis

S. chrysomallus


Aspergillus fumigatus

Inhibits growth of Pneumococcus, Streptococcus, Gonococcus; cure gonococal infection, rheumatic fever, pneumonias diseases.

Active against acid-fast and Gram-negative bacilli, cure pulmonary tuberculosis, may injure 8th cranial or auditory nerve.


Broad spectrum against bacterial and rickettsial infections, viral psittacosis.


Broad spectrum against Gram-negative organisms; cure rickettsia and some viral diseases.


Broad spectrum against bacteria, rickettsia, spirochetes, some viruses typhoid and amoebiasis; non-toxic.

Resemble the spectrum of chlorotetracycline.


More effective against bacterial and streptococal infections.



Bacteriostatic to Gram-posotive and some Gram-negative organisms that are resistant to penicillin; non-toxic.





Used adjunct to tetracyclines.

Inhibits growth of most of the fungi but not of bacteria; used in ringworm treatment.


Fungal infection like thrush.


Range of activity is similar to penicillin


Antimicrobial spectrum resembles penicillin.


Antibacterial, inhibits Gram-positive becteria and cocci.



Intestinal antiseptic; toxic.


Resembles streptomycin; but toxic to kidneys and ear.




Cure leukemia; toxic to glossitis.

Used in the treatment of willm’s tumor,

embryonic tumor of kidney in children.

Bacterial and wide range, spectrum includes Salmonella and Shigella sps.

Sir Alexander Fleming (1928)


Waksman (1943)



Ehrlic (1947)


Duggar (1947)










Clerk (1953)






Hazen and Brown (1953)



Hindustan Antibiotics, Poona


Discovered in 1957


Discovered in 1956


Dubos (1939)


Discovered in 1947






Moore et al (1954)





 Bioenergy .

The energy obtained from biological sources is called bioenergy. Bioenergy is the use of biomass (organic matter) to produce electricity, transportation fuels or chemicals. Bioenergy sources include agriculture and forestry residues and the organic component of municipal and industrial wastes.

Bioenergy is obtained from following types of biological sources :

(1) Animal energy

(2) Biofuels and Biomass

Another category of energy which is of biological origin is called as fossil fuels which includes coal, petroleum and natural gas. Energy is very critical to all developments of human welfare like transport, agriculture and industrial uses.

(1) Animal energy : Animal energy is basically of two forms :

(i) Human muscle power (HMP)

(ii) Draught animal power (DAP)

(i) Human muscle power (HMP) : It is the form of animal energy, which is used throughout the world in the form of physical work by human race like farmers in the field, women in house work and non agricultural labourers like artisans in wood work, gardeners, etc. A major part of the energy utilized today belongs to this type and it constitutes about 1/5th of the total generated electricity in India. Thus, it constitutes the significant part of energy used.

(ii) Draught animal power (DAP) : Animals are domesticated not only for providing us with food, hides and bones but they are also used in agriculture and transport. These animals play and important role in villages. India has about 84 million of work animals; 70 million bullocks; 8 million buffaloes and one million each to horses and camels. In addition mules, donkeys, elephants and yaks are also used. 50 percent of the Indian farmers have holdings less than two acres each, as a result they cannot use tractors. More than 15 million animal-drawn carts are use in India. Carts have the advantage that they can be used on all types of roads in all terrains. The energy potential of DAP is enormous. Suppose if each animal generates 0.5 horse power then the installed capacity of animals comes about 42 million horse power or 30,500 MV. This value is almost equal to total electric power generation in India. Because of poor quality of animals and outmoded designs of carts and agricultural machinery, full potential of DAP has not been realised in India. Methods recommended to achieve this are :

(a) Improved breeds of draught animals.

(b) Use of better carts.

(c) Proper management of grazing lands and pastures.

(d) Supply of nutritious fodder.

(2) Biofuels and Biomass : They are fuels of biological origin. Biofuels are major source of energy. They are renewable and if used properly and efficiently they can solve the energy problems of developing countries.

Biomass is the term applied to all materials whose origin can be traced to photosynthesis. Biomass can be used to generate producer gas, to run water pumps for irrigation, to obtain alcohol, to replace petrol, to generate biogas for cooking and lighting and to generate electricity.

Major sources of biofuels are :

(i) Wood

(ii) Agro-industrial trial residues

(iii) Energy cropping and petroplants

Ways of utilising biomass as fuel


Biomass Process Form / Source of energy produced
1. Wood Direct burning, Gasification, Carbonisation, Pyrolysis, Hydrolysis, Fermentation and Synthesis. Heat, Producer gas, Methanol, Ethanol, Charcoal gas, Oil and Charcoal.
2. Agro-industrial residues. Fermentation/Distillation, Anaerobic digestion. Biogas, Ethanol.
3. Petroleum and Oil producing plants Cracking and direct use. Petroleum products, Heating, Running engines.
4. Energy cropping Fermentation/ Distillations. Ethanol.


(i) Wood : It is the renewable and most common source of energy in use since time immemorial. Wood which is used as source of energy is called fuel wood and about 2 billion people in world are dependent upon wood as source of fuel. Excessive use of wood as fuel has led to deforestation, soil erosion, loss in fertility of soil and hence deterioration of environment.

The consumption of fuel wood was estimated at 1.7 billion m3 in 1984 of which more than two third was consumed in Asia and Africa.

  • Characteristics of good fire wood
  • It should be highly combustible.
  • It should have high calorific value and should be free of disagreeable odour.
  • The fuel wood plants should be present every where.
  • These should be easy to dry and should not split when burnt.
  • Should be non-resinous in nature and smokeless.

Good fire woods and bad fire woods

Good fire-woods Bad fire-woods
Acatica senegal (Gum Arabic) Pinus roxburghii (Chir Pine)
Acacia nilotica (Kikar) Mangifera indica (Mango)
Albizzia (Siris) Madhuca indica (Mahua)
Azadirachta indica (Neem) Bauhinia racemosa (Kachnar)
Quercus (Oak) Bombax (Red silk cotton)
Casurina (Jhau) Michelia excelsa (Champak)
Adina cordifolia (yellow teak)

Hopea (Dammar tree)

Dalbergia sisso (Shisham)

Prosopis (Jand)

Anogeissus latifolia (Axle wood, Dhawa)

Ceriops tagal (Goran)

Gmelina arborea (Gumhar)

Terminalia tomentosa (Asna)

Syzgium cumini (Jambolana Jaman)

The angiospermic wood (hard wood) is generally better than gymnospermic wood (soft wood). Soft wood produces intense heat but for shorter duration and hard wood gives uniform heat for longer periods. Bad fuelwood does not catch fire quickly, has low flame, low calorific value, gets burnt quickly, is full of smoke with offensive odour.

Due to increase in population, the demand of fuel wood is increasing day by day and this has led to fuel wood crises. In order to overcome fuel wood crisis, following methods have been suggested :

  • To grow more fuel wood trees, i.e. energy plantations.
  • Proper designing of wood stoves or chullahs in order to increase efficiency of these and hence to save energy loss.
  • Electric cremation should be enhanced.
  • Energy production form woods by different processes like carbonisation (Change of wood into carbon/charcoal by heating), gasification (change of wood into producer gas by passing steam over incandescent coke), pyrolysis (thermochemical conversion of wood into charcoal, pyroligneous acid (10% acetic acid), wood gas, wood tar, wood alcohol, etc.).
  • Energy plantations : Energy plantations mean to grow more trees for fuelwood. The uses of energy plantations are :
  • Solar energy can be stored continuously.
  • Minimum technology is required for raising the trees.
  • They are ecologically safe, economical, renewable and sufficient manpower is available to raise them.
  • The key points linked with raising of energy plantations are :

Mobilisation of land resources : to minimise the danger of loss of agricultural land for growing fuelwood, trees should be grown for fuelwood on :

  • Farmer’s land
  • Village common lands
  • Along both sides of road, canals and railway tracks
  • On degraded forests and
  • On wastelands

Over 30 million hectares of land is available in India for energy plantations, without affecting land under agricultural and industrial use.

Selection of suitable species : While selecting suitable species following criteria can be considered : 

  • The saplings should establish quickly and rapidly.
  • The species should be preferably local and wall adapted local climatic and soil conditions.
  • It should have high coppicing ability or regenerative potential. Coppicing means thick growth of branches from the stump after the aerial branches have been removed.
  • The plant should be able to grow with minimum water and fertilizer requirement.
  • The plant should draw minimum quantity of nutrients form soil.
  • Plants should be able to improve the soil quality like sterilisation, correction of alkalinity or acidity etc.
  • Plants should have the xerophytic character when grown under xeric conditions.
  • Plants should be resistant to pests and diseases.
  • Plants grown along both the sides of roads and railway tracks should be able to tolerate water logging.

Development of suitable agro-technology : Techniques of growing particular species in particular habitat must be carried out to get maximum yield. Cultivating grasses and fodder crops along with fuel wood species brings out maximum land use.

Producer gas : It is mixture of carbon, hydrogen, monoxide and oxygen. Producer gas is produced due to incomplete combusion of coal and wood. With restricted supply of air, coal and wood is burnt. Mixture gas thus produced is passed through filter to remove shoot and ashes. Now the gas is passed through coolers to condense other waste residue. Now the gas is released for industrial use. This gas is free from pollution. Raw material for producer gas is easily available and can be produced at normal temperature. The gas produced is inflammable but otherwise costly and generates less power.

(ii) Agro-industrial residues : Some methods have been devised for bioconversion of agricultural residues, industrial waste materials and animal wastes into energy. This is very important in solving the environmental pollution problems. About 28 percent of population in the developing countries uses dung and crop residues as fuel for cooking food. Thus potential fertilizer of the agricultural fields is wasted in burning. The problem can be solved by using dung to produce gobar gas (biogas) and residue can be used as manure. The aerobic fermentation of dung yields fuel as well as fertilizer.

(a) Biogas (Gobar gas) : Biogas is a gas produced from animal wastes and other organic (biological matter). The gas is produced by anaerobic fermentation of biomass. Biogas consists of 50- 70% CH4 (methane), 30- 40% CO2, 1% H2S and traces of  and CO. Calorific value of biogas is 4,429 kcal/m3, when its CH4 content is 50%.

Biogas generation is a three stage anaerobic digestion of animal and other organic wastes.


  • First stage : The facultative anaerobic micro-organisms break down the polymers into soluble monomers with the help of enzymatic hydrolysis. Lignin cannot be broken down by micro-organisms, so it remains as residue along with inorganic salts.
  • Second stage : Here the monomers become the substrate for micro-organisms. These are then converted into organic acids.
  • Third stage : In this stage soluble organic acids (acetic acid) are formed for the substrates of the last stage. Finally methanogenic anaerobic bacteria produce methane (biogas).
  • Important substrates in biogas production : Animal wastes like dung of cattle, urine and slaughter house wastes; agroindustrial wastes like oil cakes, sugar industry wastes, wastes form fruits and vegetables processing; agricultural or crop residues; human wastes (night soil); urban solid wastes and also aquatic plants like Eichhorina (water hyacinth), Wolffia, Hydrilla, Salvinia, Azolla and algae, etc.
  • In biogas production, water content is maintained at 90% at which most methanogenic bacteria are active.

The biogas so produced can be used for different purposes, can be efficiently used and stored easily. Further pathogens of faecal matter can be reduced (sanitation) and thus disease cycles are broken.(iii) Energy cropping and petroplants : These are renewable resources of energy. Growing of crops from which alcohol and other energy fuels can be produced, constitute energy cropping. Important plants of energy cropping (i.e., energy crops) are :(a) Saccharum officinarum (Sugar cane)(b) Beta vulgaris (Beet root or Chukandar)(c) Solanum tuberosum (Potato)(d) Zea mays (Maize)(e) Manihot glaziovii (Tapioca)These plants are efficient users of solar energy. These plants can be easily changed into ethanol (ethyl alcohol). In Brazil, ethanol fuel is used in automobiles (95% alcohol), where as in USA, 85-90% petrol is mixed with 10- 15% alcohol to form a new fuel called gasohol, which is used as fuel in automobiles. But slight modification is required in conventional engines to use these new fuels, i.e., ethanol and gasohol.Petroplants or Petrocrops : Latex of some plants containing long chain hydrocarbons is considered to be a good substitute for liquid fuels or petroleum. Such plants having large amount of latex with long chain hydrocarbons are called petroplants. Cultivation of petroplants is also a part of energy-cropping. Cultivation of these petrocrops was first of all done by Italians in Ethiopia about fifty years back, although actual credit for identifying the petrocrops goes to Dr. Melvin Calvin.Dr. Calvin was first to identity few petroleum plants whose products can be used in place of petrol and oil. Most of such plants belong to families asclepiadaceae, euphorbiaceae and apocynaceae. These plants are able to convert a substantial amount of photosynthates into latex.Latex contains long chained liquid hydrocarbons. These can be used directly or broken to hydrocarbons of chain length similar to the ones present in petrol.Their hydrocarbon contents can be increased by genetic manipulations (genetic engineering). But commercial production of petroleum or liquid fuel alternative (through petroplants) is in early stage.Most common petrocrops are :(a) Euphorbia antisyphilitica (b) E. caudicifolia(c) E. lathyris (Gasoline tree)(d) E. royleana(e) Calotropis procera(f) Capaifera langsdorfii (A Brazilian tree and its sap is a good alternative for diesel. About 3 litres of sap per month is produced per tree, which can be filled directly in fuel tank of diesel engine automobile).(g) Cryptostegia grandiflora(h) Pittosporum resiniferum (Petroleum nut)The use of these petroplants may reduce the pressure on liquid fuel or petroleum. New and Underutilized crops.Out of about 3,50,000 known plants at this time, a few i.e., about 100 plants are being used for fulfilling man’s daily requirements. Scientists are in search of less known and underutilized crop plants, which can be used for food and other purposes and thus exploitation of traditional plants can be reduced. Such under-utilized and under-exploited plants are known as new crops.Some of these new and underutilized crops are as follows :(1) Triticale : Triticale is the first man made cereal or crop,  which has been produced by intergeneric hybridization between common wheat (Triticum aestivum) and European rye (Secale cereale) with a view to combine characters of these two parent plants. Triticale is hexaploid, i.e, 2n = 6x = 42 (when tetraploid wheat is used) or octaploid, i.e., 2n = 8x = 56 (when hexaploid wheat is used). Triticale is the first new man-made plant to join the rank of cereals which have long evolutionary history. Triticale or triticosecale is not suitable for purpose of bread making due to low gluten content, but it is a good forge crop. Triticale is grown all over world, mainly in USSR.(2) Winged bean (Phosphocarpous tetragonolobus) : This is a herbaceous plant, which has capacity of nitrogen fixation. The tuberous roots, leaves, shoots, pods and seeds are highly nutritious due to rich source of proteins and edible for humans as well as livestock. When green, the pods, leaves and shoots are used as vegetables, unripe seeds may be used as soups and ripe seeds can be roasted. The ripe seeds contain about 34% proteins and 13% oils (similar to soyabean). Further this plant can be used as a green-manure plant, fodder plant and also as a cover crop.(3) Jojoba (Simmondsia chinensis) : This is a shrub, which is native of Mexican deserts. It is important drought desert plant, because it can survive under poor soil and low moisture conditions and hence is being grown in deserts. The seeds of this plant contain about 50% liquid wax, which is similar to sperm whale oil (spermaceti). This liquid wax was originally used in cosmetics, but now is also being used in high performance lubricants. So, growing of this plant can reduce the pressure on sperm whales, which are killed for their oil. Further growth of this plant in deserts will provide natural cover and thus enhance the economic status of the people living in these arid areas.(4) Guayule (Parthenium argentatum) : It is commonly known as carrot grass or congress grass. This is native of America and nowadays it is most troublesome terrestrial weed in India and is present in almost all states of India. The roots of this plant secret transcinnamic acid, which inhibits the growth of other plants (allelopathy). This is a shrub and can grow on poor desert soils. This plant is nowadays used in obtaining rubber, which is called Guayule rubber, which is similar to para rubber or hevea rubber. The body of this plant contains caotchouc granules, which are ingredient of rubber. The plant contains 12- 20% rubber on dry wt. basis. This plant can be a natural source of rubber in future.(5) Leucaena (Leucaena leucocephala) : It is commonly called as subabul. This is a fast growing small tree and is native of central America. This plant is nowadays being planted on a large scale under social-forestry. These plants are used as wind breaks, fire breaks, cover plant for deforested tropical regions, leaves as fodder, wood as fuel and in charcoal formation, paper pulp, rayon and timber. It is also used as shade and cover plant in coffee, tea and rubber plantations. Leucaena is a nitrogen fixing plant and leaves are good sources of green manure. It can grow on poor and worn out marginal lands.(6) Oil plant : Some potential oil yielding plants are there, which provide edible and non-edible oils after suitable treatments. Some potential oil plants are as follows :(i) Margosa or Neem : Azadirachta indica (fam. Meliaceae). It is native of Burma (Myanmar) and is widely grown tree in India. Seeds are source of margosa or neem oil with bitter taste, used in soap making.(ii) Indrayan or colocynth : Citrullus colocynthis (fam. Cucurbitaceae). It  is a perennial trailer. Roots are used in curing jaundice and urinary disease. Fruit pulp is used mediacinally as purgative and bacteriocidal. Seeds have oil.(iii) Mahua : Madhuca indica, seeds give oil used in soap making and also in cooking purposes.(iv) Buffalo or Wild gourd : Cucurbita foetidissima, it can tolerate heat and drought. Its fruit is employed as a soap substitute. The seeds are oily and edible. The underground storage roots of the plant are source of industrial starch.(v) Mustard tree or Kharjal : Salvadora perisca, seeds provide oil which is used commercially.(vi) Sal  (Shorea robusta) : Trunk yields oleoresin, which is source of ‘chua oil’ on distillation, which is used in perfumes.(7) Fooder trees : Some important fodder threes are :(i) Kikar or Babul (Acacia nilotica) : Foliage and pods are widely used for feeding goats and sheep in arid regions of India. Leaves and twigs of A. senegal provide fodder also.(ii) Siris (Albizzia lebbeck) : Young foliage contain about 20% protein and are fed to livestock(iii) Peepal (Ficus religiosa) : The leaves are lopped for elephant and cattle fodder.(iv) White mulberry (Morus alba) : The leaves which are avidly browsed by goats, cattle and sheep are deliberately lopped for fodder.(v) Basna (Sesbania grandiflora) : Cattle relish the fleshy, feathery leaves and long pods in the tropical parts of India.(8) Non-alcoholic beverages (Less-known) : Generally, non-alcoholic beverages are obtained form coffee, tea and cocoa, but there are other sources of less known beverages plants. Some of them are :(i) Catha edulis: A decoction from its leaves known as khat. Leaves and buds on chewing have stimulating effect.(ii) Cola nitida: A beverage ‘cola’  is obtained from seeds in Africa.(iii) Ilex paraguariensis (Mate) : It is source of Paraguay tea.(iv) Paullina wpana (Yaco) : Guarana seeds used an beverage in South America.Important tips

  • Both methyl alcohol (methanol) and ethyl alcohol (ethanol) can be used as fuel and automobile fuel.
  • Brazil is obtaining alcohol (Gasohol) from sugarcane while USA is getting it from maize.
  • Methanogens ane rssential for biogas production.
  • Dicotyledonous woods (called hard woods) are considered better then gymnosperms woods (called softwoods) because these burns for a longer time and provide uniform heat.
  • Coppicing means thick growth of branches form the stump after the aerial branches have been removed.
  • Only 0.2 percent of the solar energy that reaches earth’s surface is converted into biomass.
  • Animal energy is available in two forms – HMP and DAP.
  • The energy potential of DAP is enormous.
  • A major quantity of wood is used as firewood.
  • Dung is either used a fuel cakes or as fertilizer.
  • The crops which can be employed for ethanol production are called energy crops.
  • The fuels which are obtained from organic matter are called biofuels.
  • Fuel gas (methane) is obtained by anaerobic fermentation of gobar.
  • Alianthus excelsa (tree of heaven) is a fast growing timber tree suitable for wind breaks and shelter belts. Young branches are cut to feed goats.



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